JP2016086228A - Radio wave propagation analysis device and analysis method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform radio wave propagation analysis with high accuracy while suppressing significant increase in computational complexity of ray trace computation while models subjected to the radio wave propagation analysis are distributed over a local space within an entire analysis space.SOLUTION: Boundary graphic data including a local analysis space are generated from outline shape data, a ray within the entire analysis space reaching a boundary indicated by the generated boundary graphic data is searched from a first radio antenna and while referring to the outline shape data, a ray within the local analysis space from the boundary determined by the ray within the entire analysis space to a second radio antenna within the local analysis space is searched. While using the ray within the entire analysis space obtained by the search and the ray within the local analysis space, radio wave propagation of a geometrical optical path from the first radio antenna to the second radio antenna is estimated. The ray within the entire analysis space is determined from a combination of transmission information and reception information, and acquisition of the ray by the combination is restricted to a combination with which the transmission information and the reception information are present within the same presence space and a predetermined ending condition is not satisfied.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a radio wave propagation characteristic analysis apparatus and analysis method, and more particularly, to a radio wave propagation analysis apparatus and analysis method suitable for radio base station antenna arrangement design considering mutual interference between indoors and outdoors.

  In recent years, due to a rapid increase in smartphones and the like, traffic in mobile phone networks has increased, and it has become an urgent task to expand data communication capacity in networks. As a solution to this, there is a small cell configuration in which the base station area size is made smaller than that of the conventional cell design and the number of terminals to be accommodated is reduced, so that the communication capacity per terminal is afforded. However, as small cells are promoted, it will be difficult to expect the penetration of indoor base stations from outdoor base stations, so it will be necessary to reinforce indoor base stations. It is necessary to estimate.

  As described above, in the design of a small cell, it is necessary to estimate the radio wave propagation with higher accuracy. In particular, it is important to estimate the penetration of radio waves from outdoors to indoors and from indoors to outdoors. Generally, statistical methods are often used for propagation estimation methods for outdoor wide areas, but in small cell design, the shape and height of buildings have a large effect, so the ray tracing method should be used. Is desirable. In this regard, in recent years, urban topographic map data including building height information from satellite photographs and aerial photographs has become available, and analysis using the ray tracing method has become possible.

  On the other hand, there is almost no information available about the internal structure of each building, and it is necessary to measure and input them individually. Therefore, in the small cell design, ray tracing analysis using a model including wide area building outline map data and structure data in the building to be designed is necessary. In such a model, the number of elements composing the building outline map data and the number of elements composing the indoor structure are of the same scale, and the model exists at a high density in a local region where the indoor structure exists. It becomes.

  As a background art of this technical field, there is Patent Document 1. Patent Document 1 discloses a radio wave propagation characteristic for estimating a radio wave propagation characteristic in a part of an investigation target area within a cover area at high speed and with high accuracy when the coverage area of a wireless system to be estimated covers a wide area. An estimation system and a system for obtaining the method is disclosed.

WO2005 / 088886

  According to Patent Document 1, the radio wave propagation overview acquisition unit and the pseudo transmission source preparation unit are provided. Based on the estimation results of radio wave propagation over a wide area, determine the transmission power of one or more pseudo-transmission sources so as to surround the area around the local survey target area, and use the pseudo-transmission source as a new transmission source for the local survey target. A method of estimating radio wave propagation in an investigation target region by performing ray tracing calculation on the region is disclosed.

  However, since the radiation of rays from the pseudo-transmission source is largely different from the direction of rays from the actual transmission source, the radio wave penetration state from the actual transmission source is accurately estimated. It is difficult. In addition, it is impossible to estimate propagation from an indoor transmission source to the outdoors by performing re-radiation from a pseudo transmission source. In addition, even when there are a plurality of regions subject to local investigation, when estimating the radio wave propagation situation, all models are subject to calculation, so the ray trace calculation becomes large and difficult to calculate.

  The object of the present invention is to suppress radio wave propagation analysis with high accuracy by suppressing a significant increase in the amount of ray-trace calculation when the models subject to radio wave propagation analysis are scattered in a local space within the entire analysis space. An object of the present invention is to provide a radio wave propagation analyzing apparatus and method that can be used.

In order to solve the above problems, the present invention provides a radio wave propagation analysis for searching for a geometrically reachable ray from the first wireless antenna in the entire analysis space to the second wireless antenna in the local analysis space. A device,
A first database for storing schematic shape data in the entire analysis space; a second database for storing detailed shape data in the local analysis space located in the entire analysis space;
Boundary graphic input processing means for generating boundary graphic data including the local analysis space from the schematic shape data of the first database, and a ray in the entire analysis space reaching the boundary indicated by the boundary graphic data generated from the first wireless antenna. Boundary ray generation processing means for searching for and an extension for searching a ray in the local analysis space from the boundary determined by the ray in the entire analysis space to the second wireless antenna in the local analysis space with reference to the second database The radio wave propagation of the geometric optical path from the first radio antenna to the second radio antenna is estimated using the ray generation means and the ray in the entire analysis space and the ray in the local analysis space obtained by the search. Radio wave estimation processing means,
The boundary ray generation processing means obtains a plurality of transmission information on the antenna and the boundary defined on the transmission side and a plurality of reception information on the antenna and the boundary defined on the reception side together with information on the existence space, and transmits the transmission information and reception. Rays in the entire analysis space are determined from the combination of information, and the acquisition of rays by the combination performs processing limited to combinations in which transmission information and reception information are in the same existence space and do not satisfy a predetermined end condition.

In order to solve the above-mentioned problems, the present invention provides a radio wave propagation for searching for a ray that can be geometrically reached from the first wireless antenna in the entire analysis space to the second wireless antenna in the local analysis space. An analysis method,
It has rough shape data in the entire analysis space and detailed shape data in the local analysis space located in the entire analysis space,
Generate boundary graphic data including the local analysis space from the schematic shape data, search for rays in the entire analysis space reaching the boundary indicated by the boundary graphic data generated from the first wireless antenna, refer to the schematic shape data, A ray in the local analysis space from the boundary determined by the ray in the entire analysis space to the second wireless antenna in the local analysis space is searched, and the ray in the entire analysis space obtained by the search and the ray in the local analysis space are searched. Is used to estimate the radio wave propagation of the geometric optical path from the first wireless antenna to the second wireless antenna,
In searching for a ray in the entire analysis space, a plurality of transmission information of the antenna and the boundary defined on the transmission side and a plurality of reception information of the antenna and the boundary defined on the reception side are obtained together with information on the existence space thereof. Rays in the entire analysis space are determined from combinations of transmission information and reception information, and acquisition of rays by combination is limited to combinations in which transmission information and reception information are in the same existence space and do not satisfy a predetermined end condition.

  According to the present invention, in a wide-area ray trace calculation, an analysis is performed using only building outline data that does not include local structure data, and a ray trace of only local structure data is performed using this analysis result. The ray-trace calculation time can be greatly reduced.

The figure which showed the data with which a radio wave propagation analyzer is provided, and the process sequence example using this. The figure which shows an example of the hardware constitutions of a radio wave propagation analyzer in the case of implement | achieving a process procedure with a computer. The figure which shows the example of the object district of the center of Tokyo used as the object of whole analysis space data D1. The figure which shows the structural example of the predetermined floor F made into the object of local analysis space data D3. The figure which shows an example of the data table of the local analysis space data D3 which hold | maintains the three-dimensional structure information expressed by the coordinate. The figure which shows an example of the data table of the whole analysis space data D1 which hold | maintains the three-dimensional structure information expressed by the coordinate. The figure which shows the example of the table holding the boundary figure data D2 calculated | required by the process of the boundary figure input process means 101. FIG. The figure which shows the table showing arrangement | positioning of base station antenna BS. The figure which shows the table showing arrangement | positioning of the terminal station antenna BS. The figure which shows table TBS which put together the transmission group. The figure which shows table TBR which collected the reception group. The figure which shows the processing flow in the boundary ray production | generation means. The figure which shows the content of the ray trace calculation in process step S806 of FIG. The figure which shows the example of the boundary ray by an image method. The figure which shows an example of the provisional receiving point Rp defined on the boundary. The figure which shows the example of the extracted ray Br. The figure which shows an example of the intermediate product of the extended ray data D5 accumulate | stored in database DB5. The figure which shows the modification Example of an extended ray production | generation in the case of an image method. The figure which shows the deformation | transformation Example of an extended ray production | generation in the case of the launching method. The figure which shows the example of the boundary ray by a launching method. The figure which shows an example of a receiving path | route.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram illustrating data included in the radio wave propagation analysis apparatus 100 according to the present embodiment and a processing procedure example using the data. Various data used for radio wave propagation analysis in the radio wave propagation analyzing apparatus 100 in FIG. 1 is stored in the database DB. Among these, DB1 is a database of the entire analysis space data D1, DB2 is a database of boundary graphic data D2, DB3 is a database of local analysis space data D3, DB4 is a database of boundary ray D4, DB5 is a database of extended ray D5, DB6 is Each database of the radio wave propagation state data D6 is shown.

  Further, in FIG. 1, the boundary graphic input processing means 101 takes in the boundary graphic data D2 used in the subsequent analysis from the database DB1 of the entire analysis space data D1, and stores it in the database DB2 of the boundary graphic data D2. The boundary ray generation processing means 102 extracts the boundary graphic data D2 from the database DB2, generates boundary ray data D4, and stores it in the database DB4 of the boundary ray data D4.

  The extended ray generation processing means 103 generates an extended ray from the boundary ray data D4 stored in the database DB4 and the local analysis space data D3 stored in the database DB3, and stores it in the database DB5 of the extended ray data D5. The radio wave propagation estimation processing means 104 estimates the radio wave propagation state using the extended ray data D5 and stores it in the database DB5 of the radio wave propagation state data D5. The display processing unit 105 displays various data and processed data in a proper format including the finally determined radio wave propagation state.

  FIG. 2 shows an example of the hardware configuration of the radio wave propagation analyzer when the processing procedure of FIG. 1 is realized by a computer. In the radio wave propagation analyzing apparatus 100 of FIG. 2, the control unit CPU is a CPU of a computer or the like. The control unit CPU executes the processing programs of the boundary graphic input processing unit 101, boundary ray generation processing unit 102, extended ray generation processing unit 103, and radio wave propagation estimation processing unit 104 in FIG.

  DP is a display unit and is a monitor device such as a liquid crystal display. Display the contents of input data, display analysis results, etc. The display processing means 105 in FIG. 1 corresponds to the display unit DP.

  IN is an input unit such as a mouse or a keyboard. The RAM is a memory unit and is a DRAM memory or the like that holds temporary information used for analysis.

  Reference numeral M denotes a storage unit, which is a storage device such as an HDD that holds input data, analysis intermediate data, analysis results, processing programs executed by the control unit CPU, and the like. A database DB for storing various data D in FIG. 1 is also formed in the storage unit DB. Bus represents a data bus line, and connects the arithmetic unit CPU, the display unit DP, the input unit IN, the memory unit RAM, and the storage unit M to input / output data. The data bus line Bus is not limited to a bus line, and may be connected by a wired / wireless network.

  In the series of processing of FIG. 1, the entire analysis space data D1 is stored in the database DB1 and the local analysis space data D3 is prepared and stored in the database DB3 in advance, and the stored contents of the other databases DB2, DB4, DB5, and DB6. Includes secondary data created and derived based on the data D1 and D3.

  For this reason, in order to facilitate the following description, the concepts of the entire analysis space data D1 and the local analysis space data D3 are clarified in advance along specific examples. The concept of these data will be explained with a simple example. The entire analysis space data D1 is, for example, information on buildings in the center of Tokyo, its surrounding terrain, the position of the base station antenna, etc., and the local analysis space data D3 is the relevant information in the center of Tokyo. This is information on the internal structure of a building that is planned or constructed in the district. These are generally prepared as three-dimensional graphic information.

  FIG. 3 shows an example of a target district in the heart of Tokyo. In the target area, there are several buildings. Here, each building is represented by B1, B2, B3, B4, B5, B6,. The target area illustrated in FIG. 3 is expressed and stored as shown in FIG. 4 in the database DB1 of the entire analysis space data D1.

  In FIG. 4, each building in the target area is defined by name data D101, individual name data D102, figure definition data D103, and material property data D104. Among these, the name data D101 represents each building (B1, B2, B3, B4, B5, B6,... BM) in FIG. 3, and the individual name data D102 represents the name given to each building.

  Thus, the name data D101 is ID information for identifying each structure in the entire analysis space data, and is also used for association with the local analysis space data. Specifically, buildings B1 to BM in the target district in the center of Tokyo shown in FIG. 3 are listed as the name data D101. Further, one or more shape definition data D102 can be held for one name data D101. Each shape definition data identifies the shape of each building when the building (for example, B1) is configured as a set of a plurality of buildings. Alternatively, when the building is composed of a plurality of materials, one or more shape definition data D102 is held for each material portion (for example, when the material is different between the lower floors and the higher floors, the shape definition data D102 that is different for each part) It is good to set.

  The figure definition data D103 defines the size and shape of each building. When the building shape type is a rectangular parallelepiped, the figure definition data D103 is represented by a three-dimensional figure determined by its start point and end point.

  For example, for a building defined as Body1 of the building B1, this building has a vertical 55 (m) and horizontal 60 with the coordinates of the start point (0, 0, 0) and the coordinates of the end point (55, 60, 25). (M) A building with a height of 25 (m). Also, regarding the building defined as Body2 of the building B2, this building has a vertical 50 (m) and horizontal 50 with the coordinates of the start point being (80, 0, 0) and the coordinates of the end point being (130, 50, 50). (M) A building with a height of 5 (m).

  The material property data D104 is information related to the building material set for each of the name D101 and the individual name D102. The material of the building is defined by indices such as relative permittivity, relative permeability, and conductivity. Yes. These indexes affect the characteristics of radio wave propagation such as radio wave transmission, reflection, and attenuation.

  According to the material property data D104, the building B1 is defined by values such as relative permittivity (1.0), relative permeability (1.0), and conductivity (1.00E + 07). Further, according to the material property data D104, the building B2 is defined by values such as relative permittivity (6.7), relative permeability (1.0), and conductivity (0.04).

  Although not shown in FIG. 4, the database DB1 of the entire analysis space data D1 includes terrain data of the target area, base station antenna position data, and the like, which are expressed as three-dimensional graphic data examples. Yes. In the example of the target district in the center of Tokyo shown in FIG. 3, the base station antenna BS1 is provided on the roof of the building BM, and the base station antenna BS2 is provided on the third floor of the building B6.

  In the example of the target district in the center of Tokyo in FIG. 3, the portion surrounded by the dotted line A represents the storage range in the database DB1 of the entire analysis space data D1. On the other hand, the database DB3 of the local analysis space data D3 has an individual range (local analysis space) surrounded by dotted lines AB1 and AB2 in FIG. For example, the individual part surrounded by the dotted line AB1 is the eighth floor part of the building B5, and the individual part surrounded by the dotted line AB2 is the third floor part of the building B6. In the following explanation examples, the 8th floor portion of the building B6 is assumed in addition to the above two locations as the local analysis space.

  FIG. 5 shows a specific example of the floor that is the target of the local analysis space. The predetermined floor F in the example of FIG. 5 is, for example, the eighth floor of the building B5, and various devices such as a floor FR, a wall W, and a pillar P that form the predetermined floor, and a cabinet M installed on the floor. It consists of

  FIG. 6 is an example of a data table of local analysis space data D3 holding three-dimensional structure information expressing the predetermined floor of FIG. 5 by coordinates. The data table of the local analysis space data D3 illustrated in FIG. 6 is stored as information on the structure group name D301, individual name D302, three-dimensional coordinate system (X, Y, Z) D303, shape type D304, and material property D305. ing.

  In this case, a predetermined floor of the building in FIG. 3 is described as the group name D301 of the structure. In FIG. 6, B5-8F meaning the eighth floor of the building B5 and BM-3F meaning the third floor of the building BM are described as the group name D301.

  In the individual name D302, walls W1 and W2, pillars P1 and P2, and a cabinet M are illustrated as structures and devices attached to the predetermined floor (constitute the predetermined floor). The arrangement positions and sizes of these structures and devices are expressed in a three-dimensional coordinate system (X, Y, Z) based on the origin on the predetermined floor in FIG.

  In the three-dimensional coordinate system (X, Y, Z) D303, three-dimensional structure information is expressed in such a manner that the coordinate positions of two diagonal points are specified for a cubic structure such as a wall or a column. Yes. For example, the wall W1 in FIG. 5 has a length 16 (m) and a thickness 0.5 (m) where the coordinates of the start point are (0, 0, 12) and the end point is (16, 0.5, 18). ), A cubic structure having a height of 6 (m). Similarly, the pillar P1 has a start point coordinate (0, 0, 12), an end point (1, 1, 18), a length 1 (m), a thickness 1 (m), and a height 6 (m ) Cubic structure.

  Further, the material properties of the structures and devices described in the individual names D302 are described in the column D305. For example, as the characteristic value of the material constituting the wall W1, in the material characteristics in the column D305, the relative permittivity (6.7), the relative permeability (1.0), the conductivity (0.04) [S / m] Such values are shown as indicators. These material characteristic values (indexes) are not limited to these parameters as long as the characteristic values representing the reflectance, transmittance, loss, etc. of radio waves are clear.

  As described above, various devices such as the floor FR, the wall W, and the pillar P on the predetermined floor and the cabinet M installed on the floor propagate the radio waves (reflection, absorption, transmission) when performing the radio wave propagation analysis. Therefore, the database DB3 includes information on these materials. For these members, the floor FR is reinforced concrete or metal. The column P is generally reinforced concrete. The cabinet M is made of metal. Wall surfaces W1 and W2 are concrete.

  Although not shown in FIG. 6, a coordinate conversion matrix in a three-dimensional space may be used, and the result of coordinate conversion when used for analysis may be used. For example, an affine transformation matrix can express translation, rotation, enlargement, reduction, etc. in a three-dimensional space, and can hold a small amount of data of a structure having the same shape.

  These data may be input manually by an operator from the keyboard of the input unit IN shown in FIG. 2 or may be automatically obtained by connecting to other devices. . For example, a CAD drawing may be used as three-dimensional structure information by connecting to CAD (Computer Aided Design). It can also be used as an input device for spatial information by connecting to a laser range scanner, a three-dimensional recognition camera, or the like.

  Returning to FIG. 1, the boundary graphic input processing means 101 obtains boundary graphic data from the entire analysis space data D1. Here, the boundary graphic data defines the external shape of the local analysis space. In FIG. 3, taking the 8th floor (B5-8F) of the building B5 taken as an example of the local analysis space, the boundary figures are the 4 side surfaces, the upper surface (ceiling surface), and the lower surface (floor surface) of this predetermined floor. Means the six sides. In FIG. 3, the boundary graphic is expressed as “Bound”. In the example of the third floor (BM-3F) of the building BM, since the wall surface structure is complicated, the number of side surfaces is larger. In any case, the boundary graphic means the shape of the peripheral surface of a predetermined floor such as a wall, ceiling, or floor.

  In the processing of the boundary graphic input processing means 101, the shapes of the walls, ceiling, and floor of the predetermined floor F designated as the target of the local analysis space in advance are obtained by calculation. For this calculation, the three-dimensional figure definition information of the entire analysis space data D1 of FIG. 4 is used.

  FIG. 7 is a diagram showing an example of a table that holds the boundary graphic data D2 obtained by the processing of the boundary graphic input processing means 101. In the boundary graphic data D2, for each boundary graphic that represents the shape of the wall, ceiling, or floor, the type data of the shape that constitutes the shape, and the position, size, etc. in the three-dimensional space for each type are specified. It is composed of coordinate data, individual name data for identifying each figure, and the like. FIG. 7 shows an example in which the shape type is a plane, and the shape is a plane shape having a start point coordinate and an end point coordinate as diagonal lines. In addition, it is possible to define not only the plane figure shown in the example but an arbitrary three-dimensional shape.

  The table of boundary graphic data D2 is formed of a space definition information portion and a graphic definition information portion. Among these, the space definition information part is composed of at least name data D201, general analysis space link data D202, and local space link data D203.

  Of the space definition information part, the name data D201 is ID data for identifying one or more graphic definition data. For example, a specific ID is assigned with a predetermined floor as a unit of the local analysis space in FIG. 3 as a unit. In the description example of the name data D201 in FIG. 7, it is described as Bound1 and Bound2, and these are set for each predetermined floor that is the target of the local analysis space.

  Of the space definition information part, the entire analysis space link data D202 is used for associating with the structure data defined in the database DB1 of the entire analysis space data D1 of FIG. For example, by describing BM, it is possible to link to the corresponding structure information (BM) by referring to the name data D101 in the entire analysis space database DB1.

  Of the space definition information part, the local analysis space link data D203 is used for associating with the structure data defined in the database DB3 of the local analysis space data D3 of FIG. For example, by describing BM-3F, it is possible to link to the corresponding structure information (BM-3F) by referring to the name data D301 in the local analysis space database DB1.

  According to the description of this space definition information part, for example, “Bound1” which is one data of D201 is a building defined by name data “BM” and a local analysis space according to the whole analysis space link D202. The link D203 indicates the shape data of the boundary graphic representing the shape of the surrounding surface of the predetermined floor, which is associated with the indoor structure data defined with the name data “BM-3F”.

  In the present embodiment, for the sake of simplicity, the description is made with the association based on the name data. However, the association may be performed based on each three-dimensional space coordinate value in the entire analysis space. That is, it is possible to search the entire analysis space data, local analysis space data, and boundary graphic data existing in the same space and associate them with each other.

  Next, the graphic definition information part of FIG. 7 will be described. First, as an individual name of this part, the name of the boundary graphic that is the peripheral surface of the predetermined floor is described in D204. For example, BB1 is the upper surface of the upper, lower, left and right surfaces forming the predetermined floor BM-3F, and symbols are given to all boundary surfaces (predetermined floor surrounding surfaces) up to BBn1. In the graphic definition, the position and size of this plane are represented in three dimensions. The information of this portion holds information formed by the boundary graphic data input processing means 101. The boundary graphic data is implemented by a keyboard, an external data input device, or the like, and can be input by an operator or can be input by converting data created using a CAD device or the like.

  A base station antenna BS and a terminal antenna ST are laid as antennas in the target area in the center of Tokyo in FIG. On the other hand, although the antenna information is not illustrated in the entire analysis space database DB1 in FIG. 4 and the local analysis space database DB3 in FIG. 7, these are the databases (DB1,. DB3).

  FIG. 8 is a diagram showing a table representing the arrangement of base station antennas BS. This table holds base station antenna BS placement information based on the base station antenna, its placement position, and angle information.

  Among these, the information on the base station antenna is defined by the name of the base station antenna (D601), the type of antenna (D602), and the power supplied to the antenna (D603). The name D601 describes a base station antenna BS1 on the roof of the building BM and a base station antenna BS2 on the third floor of the building B6 as base station antennas in the target district in the center of Tokyo in FIG. Type D602 describes that BS1 is a dipole antenna and BS2 is a planar antenna. According to the feed power (D603), the feed power is 13, respectively. Thereby, the radiation directivity characteristics, antenna gain, and the like of the antenna are displayed.

  The arrangement information includes information on the antenna existence space (D604) and information on the place where the antenna is arranged (three-dimensional coordinates: D605). The existence space data D604 represents in which space the base station antenna BS exists. In the example of the target area in the center of Tokyo in FIG. 3, the base station antenna BS1 exists in the entire analysis space, and the base station antenna BS BS2 indicates that it exists in the local analysis space specified by “Bound1”. The existence space data D604 can be specified by inputting in advance by an operator or by determining in which space the three-dimensional coordinate value exists.

  The angle information D606 describes the angle at which the base station antenna BS is arranged, and shows an example represented by a tilt angle and an azimuth angle. The tilt angle represents the rotation angle from the horizontal plane up and down, and the azimuth angle represents the rotation angle in the horizontal plane. As a result, the direction and intensity of the radio wave radiated from the base station antenna BS can be calculated.

  Similarly, in FIG. 9, a table showing the arrangement of the terminal antennas ST is prepared. This table holds the arrangement information of the terminal antenna ST based on the terminal antenna and each information of the arrangement.

  Among these, the terminal antenna information is defined by the terminal antenna name (D701) and the antenna type (D702). In the name D701, ST1 to ST4 are described as terminal antennas in the target district in the center of Tokyo in FIG. The terminal antenna ST1 is laid between the buildings BM and B4, and the terminal antenna ST2 is provided on the third floor of the building BM and the eighth floor of the terminal antenna building B5. The antenna type D702 is a monopole antenna.

  Further, the arrangement information is configured by existence space information D703 and a place D704 where the terminal antenna is arranged, and the place is indicated by three-dimensional coordinates. Here, the information on the existence space of D703 indicates in which space the terminal antenna ST exists. According to the arrangement of terminal antennas in the target area in the center of Tokyo in FIG. 3, the terminal antenna ST1 laid between the buildings BM and B4 exists in the entire analysis space. Further, it is indicated that the terminal antennas ST2 and ST3 arranged in the predetermined floor exist in the local analysis space specified by “Bound1” and “Bound2”, respectively. The existence space data D704 is specified by determining in which space the operator is input in advance or in which space the three-dimensional coordinate value exists. In addition, as with the base station antenna BS, the installation angle of the terminal antenna ST, the feed power, and the like may be designated.

  Various antennas arranged in the target area in the center of Tokyo in FIG. 3 are organized into a transmission group mainly composed of the base station antenna BS and a reception group mainly composed of the terminal antenna ST. In the case of this arrangement, the boundaries (predetermined floor surrounding surfaces, boundary surfaces) interposed between transmission and reception are also included in the transmission and reception groups.

  FIG. 10 is a diagram showing a table TBS in which transmission groups are collected. The transmission group table TBS includes a transmission ID (D1001), a type (D1002), and a name (D1003). The transmission ID designates a unique number or symbol as appropriate for identification, and an antenna or a boundary (space definition name) is described in the type (D1002). In the name (D1003), a base station antenna BS is described as an antenna, and graphic data Bound defining a surrounding surface of a predetermined floor, which is a structure to be subjected to radio wave propagation analysis, is described as a boundary.

  FIG. 11 is a diagram showing a table TBR in which reception groups are collected. The reception group table TBR includes a transmission ID (D1101), a type (D1102), and a name (D1103). The reception ID is designated with a unique number or symbol as appropriate for identification, and an antenna or a boundary (space definition name) is described in the type (D1102). In the name (D1103), the terminal antenna ST is described as the antenna, and the graphic data Bound defining the surrounding surface of the predetermined floor, which is a structure to be subjected to radio wave propagation analysis, is described as the boundary. In addition to the receiving antenna or the boundary graphic, the reception ray information in the boundary graphic can be registered in the reception group table TBR.

  As described above, FIG. 3 shows an example of a target district in the heart of Tokyo. A database about the buildings existing here, structures and equipment existing on a predetermined floor in the building, various antennas, etc. Is prepared in advance, or data derived from the prepared data is stored in the database. These are the entire analysis space data of FIG. 4, the local analysis space data of FIG. 3, the derived boundary graphic data of FIG. 7, the base station antenna data of FIG. 8, the terminal antenna data of FIG. These data are linked to each other and used.

  FIG. 12 is a diagram showing a processing flow in the boundary ray generation means 102 of FIG. Processing step S801 represents the start of processing.

  Processing step S802 indicates the start of an iterative loop for performing the processing up to processing step S811 for the transmission group element SGi held in the transmission group table TBS of FIG. The transmission group element SGi is an element described in the transmission ID of FIG. Therefore, for example, the process is first performed on the element having the transmission ID S1, and the process up to the element S5 is sequentially performed.

  Processing step S803 indicates the start of an iterative loop for performing the processing up to processing step S811 for the reception group element RGj held in the reception group table TBR of FIG. The reception group element RGj is an element described in the reception ID in FIG. Therefore, for example, first, processing is performed on the element whose transmission ID is R1, and processing up to element R5 is sequentially performed.

  Depending on the element designation of the transmission group element SGi held in the transmission group table TBS in the processing step S802 and the element designation of the reception group element RGj held in the reception group table TBR in the processing step S803, the processing in the subsequent processing steps is as follows. It will be implemented as follows.

  That is, first, the transmission group element S1 is selected by the element designation of the transmission group element SGi, and the reception group element R1 is selected by the element designation of the reception group element RGj, and the transmission / reception status in this combination is determined. Thereafter, the transmission group element S1 and the reception group element R2 are selected to determine the transmission / reception status in this combination. Thereafter, the status determination in the combination up to the reception group element R7 for the transmission group element S1 is sequentially executed. When the processing of all the reception group elements RGj for the transmission group element S1 is completed, the transmission group element S1 is changed to the transmission group element S2, and all combinations are similarly executed. Finally, the processing is performed until the processing of all reception group elements RGj at the time of transmission group element S5 is completed. In the example of FIGS. 10 and 11, 35 combinations of 5 transmission group elements of the transmission group element SGi and 7 reception group elements of the reception group element RGj are executed.

  In processing step S804, it is determined whether the reception group element RGj is in the same existence space as the transmission group element SGi. Existence spaces described in D604 of FIG. 8 and D703 of FIG. 9 are compared from the name D1003 of the transmission group table TBS of FIG. 10 and the name D1103 of the reception group table TBR of FIG. 11, and if different, processing step S810 is performed. If it is within the same existence space, the process proceeds to processing step S805.

  For example, the name D1003 of the transmission group element S1 selected first in FIG. 10 is the base station antenna BS1, and the presence space D604 of the table of base station antennas in FIG. 8 is the entire space. On the other hand, the name D1103 of the reception group element R1 first selected in FIG. 11 is the terminal antenna ST1, and the presence space D703 of the table of terminal antennas in FIG. 9 is the entire space. Accordingly, in this case, the process proceeds to processing step S805.

  For example, regarding the transmission group element S1 and the reception group element R2 as the following combinations, the existence space D604 of the transmission group element S1 is the entire space. On the other hand, the existence space D703 of the table of terminal antennas of FIG. 9 for the terminal antenna ST2 of the name D1103 of the reception group element R2 is Bound1. Therefore, in this case, the process proceeds to processing step S810.

  It is determined whether or not the existence spaces are the same by the processing in processing step S804. If not, the process proceeds to processing step S810, and the reception group element RGj is changed until the loop ends, and the existence space is the same by the changed combination Let the sex be judged sequentially. When the existence spaces are the same, the process proceeds to processing step S805 to execute ray tracing calculation. However, even in this case, ray tracing calculation is not executed in all cases.

  In processing step S805, it is determined whether or not the end condition is satisfied when tracing from the transmission group element SGi to the reception group element RGj. When the end condition is satisfied, the ray trace calculation is not executed. The termination condition here is a case where the number of repetitions when the transmission group element SGi and the reception group element RGj are both boundary conditions exceeds the number of times specified in advance. If the end condition is satisfied, the process proceeds to step S810. If not satisfied, the process of step S806 is performed.

  Note that this termination condition defines the number of repetitions when both the transmission group element SGi and the reception group element RGj are boundary conditions, and thus either the transmission group element SGi or the reception group element RGj is an antenna. In some cases, there is no limit on the number of repetitions. In this way, in the ray trace calculation over a wide area, the analysis is performed using only the building outline data that does not include the local structure data, and the ray trace of only the local structure data is performed using this analysis result. Thus, it is possible to significantly reduce the ray trace calculation time.

  Process step S806 represents a process of performing ray trace calculation in the existence space from the transmission group element SGi to the reception group element RGj. Details of this processing will be described with reference to another flow shown in FIG.

  In process step S807, it is determined with reference to FIG. 11 whether the receiving group element RGj is a receiving antenna or a boundary graphic. If it is a receiving antenna, the process proceeds to processing step S809, and if it is a boundary graphic, the process proceeds to processing step S808.

  Processing step S808 indicates processing when the reception group element RGj is a boundary graphic, and the ray trace result SB (transmission group element SGi, reception group element RGj) is registered in the next transmission group as reception ray information in the boundary graphic. Perform the process.

  Processing step S809 shows processing when the reception group element RGj is a reception antenna, and shows processing for outputting the ray trace result SR (transmission group element SGi, reception group element RGj) as a reception result at the reception antenna.

  Process step S810 indicates a loop end process for the reception group element RGj of the reception group. If all the processes included in the reception group are completed, the process proceeds to process step S811, and if there are remaining reception group elements RGj, the process returns to process step S803.

  Process step S811 shows a loop end process for the transmission group element SGj of the reception group. If all the processes included in the reception group are completed, the process proceeds to process step S812, and if there are remaining reception group elements SGj, the process returns to process step S802.

  Processing step S812 is processing for determining whether or not a transmission group element is registered in the next transmission group. If registered, the process proceeds to process step S813. If not registered, the process proceeds to process step S814.

  Process step S813 shows the process which replaces the element registered into the following transmission group SGN with the transmission group SG. In addition, SGN is in a state of 0 elements.

  Process step S814 indicates the end of the process.

  As described above, in the wide-area ray trace calculation (boundary ray generation processing means 102 in FIG. 1), the analysis is performed using only the building outline data not including the local structural data, and then this analysis is performed. By using the result and performing ray tracing of only the local structure data, it is possible to significantly reduce the ray tracing calculation time.

  FIG. 13 shows the contents of substantial ray-trace calculation. 12 shows processing for performing ray tracing calculation in the processing step S806 of FIG. 12 by an image method. Here, the image method will be described with reference to FIGS. 14 and 15 before the description of FIG.

  FIG. 14 shows an example of a boundary ray by the image method. In FIG. 14, the building B (B1 to B10, BM) existing in the entire analysis space is illustrated in a plane, and the boundary Bound1 of the eighth floor from the building BM including the base station BS1 to the building B5 on the receiving side. -Shows a route (path P) to B1 and Bound1-B2.

  According to this example, the path P1 is a direct route that reaches directly from the base station BS1 to the receiving building B5, the third floor boundary Bound1-B1, and the path P2 is a reflection at the boundary between the base station BS1 and the building B10, building B2. The reflection route, the path P3, which reaches the boundary Bund1-B1 of the receiving building B5 and the eighth floor via the path B3 passes through the reflection at the boundary between the building B3 and the building B5 from the base station BS1 and receives the boundary Bund1-B1 of the eighth floor. It is a reflection route to reach. The path P4 is also a reflection route along the same path as the path P3, but is different in that it reaches the reception building B5 and the boundary Bound1-B2 of the eighth floor. A path that reaches the boundary Bound1-B1 is indicated by a solid line, and a path that reaches the boundary Bound1-B2 is indicated by a dotted line. FIG. 14 shows a top view, but it is actually understood as a three-dimensional notation.

  In the case of this image method, one or more temporary reception points Rp are defined on the boundaries Bound1-B1 and Bound1-B2, and the path P to the temporary reception point is calculated as a ray Br. The ray trace calculation can also be performed by a launching method other than the image method. In the case of the launching method, the one that reaches the boundary surface Bound1-B1 or Bound1-B2 from the base station BS1 is used. Represented as ray Br.

  FIG. 15 shows an example of the provisional reception points Rp defined on the boundaries Bound1-B1 and Bound1-B2. One point (Rp1) is located on the boundary Bound1-B1 on the third floor of the building B5, and 2 is indicated on Bound1-B2. It is assumed that one point (Rpm) is set for the points (Rp2, Rp3) and BoundB1-Bn. Here, the provisional reception point Rp is a point on each figure constituting the boundary graphic data, and is treated as a reception point when calculating by the image method. The temporary reception points Rp can be arranged in a mesh shape at the center of gravity of the figure or at intervals specified in advance. Further, by arranging the temporary reception point Rp at a position corresponding to an opening such as a window in the local space analysis data, it is possible to efficiently extract a dominant ray.

  FIG. 16 is a diagram showing an example of the extracted ray Br, and shows boundary rays Br1, Br2, and Br3 that reach from the base station BS1 to the receiving building B5 and the boundary Bound1 on the third floor. The boundary rays Br1, Br2, and Br3 are data extracted from the paths P1, P2, P3, and P4 in FIG. 14, and each boundary Bound1-B1, Bound1-B2,. A ray Br that reaches any one of Bound1-Bm and that follows the same route is a single boundary ray.

The information on the boundary ray Br obtained in this way holds the average value of the radiation angles (θ, φ) for the rays from the base station BS1 on the same route reaching the temporary reception point Rp. In addition, as a method for calculating the variance (σ ² ), for example, a value at which the variance (σ ² ) is πR ² with respect to the average value R of the projected area with respect to the arrival direction with respect to the boundary figure where each arriving temporary reception point Rp exists. Is calculated as variance (σ ² ) and held as boundary ray data.

  In determining a ray, it is effective to limit the number of routes on the way. For example, in the case of FIG. 16, the rays Br2 and Br3 have undergone reflection twice, but for example, in the case of a ray that has experienced four or more reflections, a treatment such as non-adoption is effective. This correspondence can be handled in the same manner when a ray generated in the local space is adopted. These limit times should be entered separately.

  Returning to FIG. 13, the process of performing ray trace calculation in the process step S806 of FIG. 12 by the image method will be specifically described. Here, ray tracing calculation from the transmission group element SGi to the reception group element RGj is performed by an image method.

  Processing step S1201 in FIG. 13 indicates the start of processing.

  In process step S1202, the reception point list RL is initialized, and processing for registering all reception points rj in the reception group element RGj is performed. Specifically, referring to the type (D1102) of FIG. 11, if the reception group element RGj is a reception antenna, it can be registered as it is. Referring to the type (D1102) of FIG. 11, when the reception group element RGj is a boundary graphic, the sampling point in each graphic element included in the reception group element RGj is registered in the reception point list.

  Process step S1203 represents a process of initializing the additional route search list PL. The list is emptied and the default route “direct wave” is registered.

  In step S1204, it is determined whether or not the transmission group element SGi is a boundary graphic. If the transmission group element SGi is a boundary graphic, the process proceeds to processing step S1205; otherwise, the process proceeds to processing step S1206.

  Processing step S1205 is processing for additionally registering a route included in the received ray information of the boundary graphic in the additional search list PL when the transmission group element SGi is a boundary graphic.

  Processing step S1206 indicates the start of a loop in which the processing from processing step S1207 to processing step S1210 is repeated for each element PLk of the route search list PL.

  Processing step S1207 indicates the start of a loop in which the processing from processing step S1208 to processing step S1209 is repeated for each element RLl of the reception point list RL.

  Processing step S1208 performs a process of additionally searching for a via point that can be added to the additional search path PLk for the structure in the existence space of the transmission group element SGi and the reception group element RGj. As a result, a list SRL (SGi, RLl) of additional paths that reach the RLl by adding a transit point from the transmission group element SGi to PLk is obtained.

  Processing step S1209 indicates the end of the loop processing for the additional search route PLk. Processing step S1210 indicates the end of the loop processing for RL1 of the reception point list RL.

  Processing step S1211 is processing step S for determining whether or not the reception group element RGj is a boundary graphic. If it is a boundary graphic, the processing of step S1212 is performed, otherwise the processing proceeds to processing step S1213.

  Processing step S1212 is a process for unifying the received ray information that arrives in the same route order with respect to the received ray information in the boundary graphic RGj. This eliminates the need to search for duplicate routes when registering the next two transmission groups.

  As described above, in the wide-area ray trace calculation in the boundary ray generation processing unit 102, the ray trace analysis is performed using only the building outline data not including the local structure data. There is an effect that can be significantly reduced.

  Returning to FIG. 1, the processing content of the extended ray generation processing means 103 as the next processing means will be described. The processing here is basically executed by changing the processing flow in FIGS. 12 and 13. In the wide-area ray trace calculation in the boundary ray generation processing unit 102, boundary rays Br1, Br2, and Br3 reaching the boundary Bound 1 of the receiving building B5 and the third floor from the base station BS1 are calculated. Perform local ray-trace calculations within the building.

  For this reason, the database of the local analysis space data D3 is referred to for the processing of the extended ray generation processing means 103. In addition, in the processing flow of FIG. 12, the transmission group element SGi held in the transmission group table TBS is replaced with information on the boundary Bound1 of the reception building B5 and the third floor. Further, the reception group element RGj held in the reception group table TBR is replaced with information of the terminal antenna ST1 in the local space or the boundary Bound1 of the third floor. The processing steps to be replaced are S802, S803, S806, S813, etc. in FIG. After replacing the transmission / reception relationship with the relationship in the local space in this way, the processes in FIGS. 12 and 13 are re-executed.

  Through a series of processing by the boundary example generation processing means 102 and the extended ray generation processing means 103, the route from the base station BS1 to the reception building B5 and the terminal antenna ST1 in the third floor can be calculated as a ray. .

  FIG. 17 shows an example of an intermediate product of the extended ray data D5 finally obtained and accumulated in the database DB5 as the analysis result in the wide area and the local area. D501 is a boundary ray ID, D502 is a transmission ID, D503 is a reception boundary area, D504 is a reception boundary graphic, D506 and D507 are radial angles, and D508 is a dispersion value.

  As described above, in the wide-area ray trace calculation in the boundary ray generation processing unit 102, the ray trace analysis is performed using only the building outline data not including the local structural data. By performing ray tracing of only the local structure data in the extended ray generation processing means 103, there is an effect that the ray tracing calculation time can be greatly reduced.

  FIG. 18 shows a modified example of the extended ray generation in the case of the image method, and the series of processes of FIG. 12 may be executed as shown in FIG. First, the first processing step S901 in FIG. 18 indicates the start of processing.

  In process step S902, the reception point list RL and the additional route search list PL (prefix list) are cleared. In processing step S903, it is determined whether or not the reception point registered in the reception group element RGj is a boundary graphic. If the reception point is a boundary graphic, the process proceeds to processing step S904 and is registered in the reception group element RGj in the reception point list RL. Each temporary reception point (Rpk) is added. If it is not a boundary graphic, the process proceeds to processing step S905, and the description content of the reception group element RGj is added to the reception point list RL.

  In processing step S906, it is determined whether or not the transmission point registered in the transmission group element SGi is a boundary graphic. If the transmission point is a boundary graphic, the process proceeds to processing step S907, and each boundary is added to the additional route search list PL (prefix list). Register a ray. If it is not a boundary graphic, the process moves to step S908, and the transmission point SGi registered in the transmission group element SGi is registered in the additional route search list PL (prefix list).

  In process step S909, the iterative process is executed for the additional route search list PL (prefix list), and then in process step S910, the iterative process is executed for the reception point list RL. In processing step S911 for the combinations determined by these, an object in the existence space is added to each element PLk of the additional route search list PL (prefix list) to create an image method route candidate PCk.

  In processing step S912, it is determined whether or not the added image method path candidate PCk and each element RLI of the reception point list RL exist. If they exist, a path is added to the ray trace result SB (SGi, RGj) in processing step S913. To do. After the processing steps S912 and S913, the iterative process is terminated for each element RLI of the reception point list RL in the process step S914, and further, the iterative process is performed for each element PLk of the additional route search list PL (prefix list) in the process step S915. Exit.

FIG. 19 shows a modified embodiment of extended ray generation in the case of the launching method. The series of processes in FIG. 12 may be executed as shown in FIG. When the process of FIG. 19 is compared with the process by the image method of FIG. 18, only process step S900 is different. In processing step S900, for each element PLk of the additional route search list PL (prefix list), a new ray is generated in the range of dispersion (σ ² ) in the radial direction angle (θ, φ), and launched into the existence space. To implement.

FIG. 20 shows an example of a boundary ray by the launching method. Here, the arrangement conditions for buildings and the like are the same as in FIG. 14, and an example of the path P3 is shown. In the launching method, rays are radiated from the base station antenna BS1, which is a transmission point, at an equal angular radiation angle density, and thus there is a possibility that a plurality of paths P on the same route reach different points on the boundary graphic. The path P3 and the path P3-1 are routes that reach the two points of the receiving building B5 and the boundary Bound1-B1 on the eighth floor through reflection at the boundary between the building B3 and the building B5 from the base station BS1. Similarly, the path P4 from the receiving route B5 to the boundary Bound1-B2 of the eighth floor on the same route is determined to be the same type as the path reaching the boundary area Bound1, as in the image method.
The average value and variance (σ ² ) of the radiation angles (θ, φ) from the base station BS1 of the same route reaching the boundary surface are calculated and held as boundary ray data.

  Returning to FIG. 1, the radio wave propagation estimation processing means 104 calculates the reception status at the receiving antenna based on the propagation path obtained as described above. FIG. 21 shows an example of a reception path. When the transmission antenna reaches diffraction point 1, transmission point 1, reflection point, transmission point 2, diffraction point 2, and reception antenna, the distance between each part, transmission It shows how the receiving antenna gain is obtained from the antenna gain or the like. Since specific calculation formulas and concepts are described in detail in “Radio Wave Propagation Handbook” (ISBN4-89808-012-X) issued by Realize, detailed description here is omitted.

100: Radio wave propagation analysis device 101: Boundary graphic input processing means 102; Boundary ray generation processing means 103: Extended ray generation processing means 104: Radio wave propagation estimation processing means DP: Display means DB1: Whole analysis space data database DB2: Boundary graphic data Database DB3: Local analysis space data database DB4: Boundary ray data database DB5: Radio wave propagation state data database

Claims (14)

A radio wave propagation analysis device for searching for a ray that can be geometrically reached from a first wireless antenna in a global analysis space to a second wireless antenna in a local analysis space,
A first database for storing schematic shape data in the overall analysis space; a second database for storing detailed shape data in a local analysis space located in the overall analysis space;
Boundary graphic input processing means for generating boundary graphic data including the local analysis space from the schematic shape data of the first database, and an overall analysis from the first wireless antenna to the boundary indicated by the generated boundary graphic data Boundary ray generation processing means for searching for rays in the space, and in the local analysis space from the boundary determined by the rays in the entire analysis space to the second wireless antenna in the local analysis space with reference to the second database Using the extended ray generating means for searching for the ray of the first and second rays and the ray in the entire analysis space and the ray in the local analysis space obtained by the search from the first wireless antenna to the second wireless antenna. A radio wave propagation estimation processing means for estimating radio wave propagation of the geometric optical path;
The boundary ray generation processing means obtains a plurality of transmission information on the antenna and boundary defined on the transmission side and a plurality of reception information on the antenna and boundary defined on the reception side together with information on the existence space, The ray in the entire analysis space is determined from the combination of reception information, and the acquisition of the ray by the combination is limited to the combination in which the transmission information and the reception information are in the same existence space and does not satisfy the predetermined end condition. A radio wave propagation analyzer characterized in that it performs. The radio wave propagation analyzer according to claim 1,
The term “in the same existence space” means that both transmission information and reception information related to the combination are positioned in the entire space. The radio wave propagation analyzer according to claim 1 or 2,
The radio wave propagation analyzing apparatus according to claim 1, wherein the predetermined termination condition is to limit a processing count when both transmission information and reception information related to the combination are related to a boundary. The radio wave propagation analyzer according to any one of claims 1 to 3,
A radio wave propagation analyzing apparatus, wherein a ray in the entire analysis space or a ray in the local analysis space is employed as a ray when the number of reflections is equal to or less than a predetermined rank. The radio wave propagation analyzer according to any one of claims 1 to 4,
The boundary ray generation processing means applies an image method in searching for rays in the entire analysis space, and stores event information of a route reaching the boundary from the first wireless antenna position as boundary ray information. A radio wave propagation analyzer. The radio wave propagation analyzer according to any one of claims 1 to 5,
The first database for storing the rough shape data in the entire analysis space stores the attenuation characteristics in consideration of the characteristics of the structure outside the boundary surface in association with the boundary surface in advance. A radio wave propagation analysis device. The radio wave propagation analyzer according to any one of claims 1 to 6,
The boundary ray generation processing means applies a ray launch method in searching for rays in the entire analysis space, and stores event information of a route reaching the boundary from the first wireless antenna position as boundary ray information. A radio wave propagation analyzer. A radio wave propagation analysis method for searching for a ray that can be geometrically reached from a first radio antenna in a global analysis space to a second radio antenna in a local analysis space,
The rough shape data in the overall analysis space, and the detailed shape data in the local analysis space located in the overall analysis space,
Boundary graphic data including the local analysis space is generated from the schematic shape data, a ray in the entire analysis space reaching the boundary indicated by the generated boundary graphic data from the first wireless antenna is searched, and the schematic shape The data is searched, a ray in the local analysis space from the boundary determined by the ray in the entire analysis space to the second wireless antenna in the local analysis space is searched, and the ray in the entire analysis space obtained by the search is searched. And using the ray in the local analysis space, estimating the radio wave propagation of the geometric optical path from the first wireless antenna to the second wireless antenna,
When searching for a ray in the entire analysis space, a plurality of transmission information on the antenna and boundary defined on the transmission side and a plurality of reception information on the antenna and boundary defined on the reception side are obtained together with information on the existence space. The ray in the entire analysis space is determined from the combination of the transmission information and the reception information, and the acquisition of the ray by the combination is a combination in which the transmission information and the reception information are in the same existence space and the predetermined end condition is not satisfied. Radio wave propagation analysis method characterized by limiting. The radio wave propagation analysis method according to claim 8,
The term “in the same existence space” means that both transmission information and reception information related to the combination are positioned in the entire space. The radio wave propagation analysis method according to claim 8 or 9, wherein
The radio wave propagation analysis method characterized in that the predetermined end condition is to limit the number of times of processing when both transmission information and reception information related to a combination are related to a boundary. The radio wave propagation analysis method according to any one of claims 8 to 10,
A radio wave propagation analysis method, wherein a ray in the entire analysis space or a ray in the local analysis space is adopted as a ray when the number of reflections is equal to or less than a predetermined rank. The radio wave propagation analysis method according to any one of claims 8 to 11,
The boundary ray generation processing means applies an image method in searching for rays in the entire analysis space, and stores event information of a route reaching the boundary from the first wireless antenna position as boundary ray information. Radio wave propagation analysis method. The radio wave propagation analysis method according to any one of claims 8 to 12,
The first database for storing the rough shape data in the entire analysis space stores the attenuation characteristics in consideration of the characteristics of the structure outside the boundary surface in association with the boundary surface in advance. Radio wave propagation analysis method characterized by The radio wave propagation analysis method according to any one of claims 8 to 13,
The boundary ray generation processing means applies a ray launch method in searching for rays in the entire analysis space, and stores event information of a route reaching the boundary from the first wireless antenna position as boundary ray information. Radio wave propagation analysis method.

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